To prevent fuel vapors from entering the atmosphere, a fuel vapor emission control system can be used to capture and store vapors produced inside the vehicle fuel system. The vapors are then directed to an intake of the vehicle engine where they are burned. However, fuel vapor emission control systems are becoming increasingly more complex, in large part in order to comply with environmental and safety regulations imposed on manufacturers of gasoline powered vehicles. Certain regulations affecting the gasoline-powered vehicle industry require that fuel vapor emission from a fuel tank's ventilation system be stored during periods of an engine's operation. In order for the overall vapor emission control system to continue to function for its intended purpose, periodic purging of stored hydrocarbon vapors is necessary during operation of the vehicle. In addition to fuel vapor recovery, to further prevent vapors from entering the atmosphere, the fuel vapor emission control system may be required to detect a leak in the fuel system or determine hydrocarbon concentration of the vapors.
The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.